Rational and Irrational Risks

In a Wired essay on the psychology of risk, Bruce Schneier argues that humans are not yet as rational as we should be:

People are not computers. We don't evaluate security trade-offs mathematically, by examining the relative probabilities of different events. Instead, we have shortcuts, rules of thumb, stereotypes and biases -- generally known as "heuristics." [...]

When you examine the brain heuristics about risk, security and trade-offs, you can find evolutionary reasons for why they exist. And most of them are still very useful. The problem is that they can fail us, especially in the context of a modern society. Our social and technological evolution has vastly outpaced our evolution as a species, and our brains are stuck with heuristics that are better suited to living in primitive and small family groups.

And when those heuristics fail, our feeling of security diverges from the reality of security.

Link: Wired News: Human Brain a Poor Judge of Risk.

I think Schneier may be the best writer we have on issues of security, but when it comes to psychology I wonder about his authority.  The current fad for evolutionary psychology has people over-applying it and making all sorts of unscientific conjectures.  (Just to be totally clear: I'm not criticizing evolution, just some aspects of the relatively new field of evolutionary psychology.)  Do we really know so much about people that we can isolate behaviors so cleanly and say definitively that they serve no purpose at all?

Schneier seems to assume that a more orderly, rational brain would necessarily be a better, more evolved one.  He writes:

The human brain is a fascinating organ, but it's an absolute mess. Because it has evolved over millions of years, there are all sorts of processes jumbled together rather than logically organized. Some of the processes are optimized for only certain kinds of situations, while others don't work as well as they could. There's some duplication of effort, and even some conflicting brain processes.

But these statements are not rational and neutral; they're judgments coming from a very particular worldview.  One could argue (perhaps even using evolutionary psychology gimmicks) that a messy brain has its advantages, as might all of these other aspects he criticizes.  Do we really know?  Sure it's good to educate ourselves about risks and try to be more rational, but to suggest that we know how a perfect brain might be built to handle risk seems quite a leap.